Ensure post not run twice in form controller tests

spec/requests/form_controller_spec.rb

@@ -763,6 +763,7 @@ RSpec.describe FormController, type: :request do
             }
           end
 
+          context "when the log will not be a duplicate" do
             before do
               post "/lettings-logs/#{lettings_log.id}/#{page_id.dasherize}", params:
             end
@@ -783,8 +784,9 @@ RSpec.describe FormController, type: :request do
               expect(whodunnit_actor).to be_a(User)
               expect(whodunnit_actor.id).to eq(user.id)
             end
+          end
 
-          context "and the answer makes the log a duplicate" do
+          context "when the answer makes the log a duplicate" do
             context "with one other log" do
               let(:new_duplicate) { create(:lettings_log) }
 
@@ -880,7 +882,7 @@ RSpec.describe FormController, type: :request do
             end
           end
 
-          context "and the answer makes the log stop being a duplicate" do
+          context "when the answer makes the log stop being a duplicate" do
             context "when the log had one duplicate" do
               let(:old_duplicate_set_id) { 130 }
               let!(:old_duplicate) { create(:lettings_log, duplicate_set_id: old_duplicate_set_id) }